33 Airworthiness Directives: 26 airplane, 3 engine, 4 appliance.
AD 97-03-03 · published Feb 3, 1997, effective Mar 23, 1997
B-N Group Ltd. Airplanes
This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Britten-Norman BN-2, BN-2A, and BN-2B series airplanes that do not have generator terminal diodes installed with Modification NB/M/1571. This action requires removing the terminal diodes that have a 70 amp direct current (DC) Generation System, which is referred to as Modification NB/M/1148, and installing Modification NB/M/1571, which consists of new terminal diodes with a higher amp rating. Reports from operators that one or both diodes were failing prompted this action. The actions specified by this AD are intended to prevent loss of electrical power to the navigation, communications, and light systems, which could impair the pilot's ability to maintain control of the airplane.
AD 97-03-04 · published Feb 3, 1997, effective Mar 10, 1997
The Boeing Company Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 727 and 737 series airplanes, that requires replacing the fuel cap assembly with a new assembly on the inlet fitting at the inside top of the Boeing-designed auxiliary fuel tank(s). This amendment also requires installing certain new placards once the replacement action is accomplished. This amendment is prompted by reports that the fuel cap assembly, due to its design, became loose and allowed fuel to enter the deactivated auxiliary fuel tanks on in-service airplanes. The actions specified by this AD are intended to prevent unwanted fuel transferring to the deactivated auxiliary fuel tanks, due to the problems associated with a loose fuel cap assembly.
AD 97-03-05 · published Feb 3, 1997, effective Mar 10, 1997
The Boeing Company Airplanes
This amendment supersedes an existing airworthiness directive (AD), applicable to certain McDonnell Douglas DC-9 series airplanes, that currently requires repetitive visual inspections to detect corrosion and cracking of the fuselage upper skin and frames in the area of the loop antenna assemblies of the automatic direction finder (ADF), and repair, if necessary. This amendment adds a requirement to perform a visual and an eddy current inspection of the fuselage forward upper skin under the antennas, followed by the reinstallation of the ADF antennas using an improved procedure. This amendment is prompted by the development of a modification of the ADF antenna installation that constitutes terminating action for the required repetitive visual inspections. The actions specified by this AD are intended to prevent rapid decompression of the fuselage, significant structural damage, and subsequent reduced structural integrity of the airplane, due to problems associated with corrosion and fatigue cracking in the subject area.
AD 97-03-07 · published Feb 4, 1997, effective Mar 11, 1997
Raytheon Model Hawker 800 and 1000 and Model DH/BH/HS/BAe 125 Series Airplanes (Including Major Variants C29A, U125, and U125A Series Airplanes)
This amendment supersedes an existing airworthiness directive (AD), applicable to certain Raytheon Model BAe 125-1A through -1000A series airplanes and Model Hawker 800 and 1000 airplanes, that currently requires repetitive inspections to detect fatigue cracking of the sidestay jack pivots of the main landing gear (MLG), and replacement of the sidestay jack pivot assemblies with new assemblies. This amendment adds a requirement to replace the sidestay jack pivot assemblies with new, improved assemblies; when accomplished, this replacement would terminate the inspection requirements of the AD. This amendment also expands the applicability of the existing AD to include additional airplanes. The actions specified by this AD are intended to prevent fatigue fracturing of the sidestay jack pivots of the MLG, which could result in the inability of the MLG to deploy and a consequent wheels-up landing.
AD 97-03-11 · published Feb 7, 1997, effective Mar 14, 1997
Saab Model SAAB 2000 Series Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB 2000 series airplanes, that requires modification and sealing of the firezone compartment of the nacelle of the left and right engines. This amendment is prompted by reports indicating that firezone compartments have not been completely sealed. The actions specified by this AD are intended to prevent flame, fuel, and vapor from entering compartments behind the firezone compartment. This condition, if not corrected, and if combined with a fire source in the firezone compartment, could result in an uncontrollable fire outside the firezone compartment.
AD 97-03-14 · published Feb 7, 1997, effective Mar 14, 1997
The Boeing Company Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 737-300 series airplanes, that requires an inspection to detect fatigue cracking, base trim, and upper flange over-trim of the pulley brackets of the aileron control cables. This amendment also requires, if necessary, replacement of the pulley brackets with new pulley brackets, and replacement of the two button-head rivets with flush-head rivets. This amendment is prompted by a review of the design of the flight control systems on Model 737 series airplanes. The actions specified by this AD are intended to prevent fatigue cracking or fracturing of the pulley brackets, which could result in slack in the cables and consequent reduced ability of the flightcrew to control the aileron.
AD 97-03-15 · published Feb 7, 1997, effective Mar 14, 1997
The Boeing Company Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-9 and Model DC-9-80 series airplanes, Model MD-88 airplanes, and C-9 (military) series airplanes, that requires modification of the girt and firing lanyard stowage. This amendment is prompted by reports of in-cabin inflation of certain evacuation slides due to the impingement of the galley service cart on the slide girt and firing lanyard. The actions specified by this AD are intended to prevent inadvertent inflation of the evacuation slides inside the cabin, which could contribute to injury of passengers and/or flightcrew in the passenger cabin.
AD 97-03-16 · published Feb 7, 1997, effective Mar 14, 1997
The Boeing Company Airplanes
This amendment supersedes an existing airworthiness directive (AD), applicable to certain McDonnell Douglas Model MD-11 and MD-11F series airplanes, that currently requires, among other things, repetitive visual inspections to detect discrepancies of the fuel pipe of the fuel transfer system of the tail tank and associated mounting bracket located in the aft fuselage compartment. That AD was prompted by reports of cracking or bending of the fuel pipe mounting support and/or attaching bracket in the aft fuselage compartment due to a fuel pressure surge that caused repetitive loading of this area. This amendment adds a requirement to install a restraint on the tail tank fuel pipe, which would terminate the repetitive visual inspections. The actions specified by this AD are intended to prevent such cracking/bending, which could expose the fuel pipe coupling O-ring. An exposed O-ring could lose its sealing effect and could allow a fuel leak in the aft fuselage compartment, which would present a fire hazard.
AD 97-03-17 · published Feb 7, 1997, effective Mar 14, 1997
The Boeing Company Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to all Boeing Model 747 and 757 series airplanes, that requires repetitive visual inspections to detect discrepancies of the wire terminal assembly, electrical connector, and wire insulation on the fuel pump; and replacement of the fuel pump with a new fuel pump, if necessary. This amendment also requires repetitive insulation resistance tests of the fuel pump wiring. This amendment is prompted by reports of fuel leaks at the fuel boost and override/jettison pumps due to corrosion. The actions specified by this AD are intended to prevent such a fuel leakage, which could result in a fire at the location of the affected fuel pump.
AD 96-26-05 · published Feb 12, 1997, effective Feb 12, 1997
Fokker Services Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to all Fokker Model F27 Mark 100, 200, 300, 400, 500, 600, and 700 series airplanes, that requires an inspection to detect cracking of the torque tube assembly of the left-hand (LH) elevator and surrounding structure; and to detect loose or sheared rivets in that assembly. This amendment also requires either replacement or repair of discrepant parts, as appropriate. This amendment is prompted by a report of fatigue cracking found on the torque tube support of the LH elevator. The actions specified by this AD are intended to ensure that cracking is detected and corrected in a timely manner so as to prevent failure of the torque tube or its support structure, which could result in reduced controllability of the airplane.
AD 97-03-18 · published Feb 12, 1997, effective Mar 19, 1997
Saab AB, Saab Aerosystems Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB SF340A, SAAB 340B, and SAAB 2000 series airplanes, that requires replacement of the hubcap drive coupling of the main wheel with an improved coupling. This amendment is prompted by reports of unexpected decreases in the pressure of the main wheel brake due to incorrect engagement between the main wheel coupling and the wheel speed transducer, which can result in false signals being sent to the anti-skid control box. The actions specified by this AD are intended to prevent loss of brake effectiveness due to a decrease in the pressure of the main wheel brake.
AD 97-03-19 · published Feb 12, 1997, effective Mar 19, 1997
Boeing Model 747 Series Airplanes
This amendment supersedes an existing airworthiness directive (AD), applicable to certain Boeing Model 747 and 767 series airplanes, that currently requires inspection of the door opening thrusters and door opening/snubbing actuators for proper oil quantity, and modification of the off-wing compartment latching assemblies. This amendment adds a requirement for replacement of the currently installed door opening thrusters with new, improved thrusters for Model 747 series airplanes. This amendment also removes Model 767 series airplanes from the applicability of the AD, since those airplanes are addressed currently in a separate AD. This amendment is prompted by reports indicating that the requirements of the existing AD do not adequately detect leakage of fluid from the actuators. The actions specified by this AD are intended to prevent such leakage, which could result in failure of the escape slide to deploy; such failure could delay and possibly jeopardize the successful emergency evacuation of an airplane.
AD 97-02-08 R1 · published Feb 13, 1997, effective Mar 4, 1997
McDonnell Douglas Model DC-9, DC-9-80 and C-9 (Military) Series Airplanes, and Model MD-88 Airplanes
This document corrects information in an existing airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model DC-9, DC-9-80 and C-9 (military) series airplanes, and Model MD-88 airplanes. The AD currently requires either the installation of external protective doublers between the outboard flight spoiler actuators and the aft spar webs of the wings, or replacement of the pistons of the outboard flight spoiler actuators with improved pistons. This action corrects a part number specified for flight spoiler actuator assembly that is acceptable for installation on these airplanes. This action is necessary to ensure that operators who previously have installed assemblies with this part number will be given proper credit for that installation, and will not be required to perform additional, unnecessary work to comply with the requirements of the AD.
AD 97-04-01 · published Feb 14, 1997, effective Mar 21, 1997
Boeing Model 737 Series Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 737 series airplanes, that requires modification of the aileron centering spring and trim mechanism. This amendment is prompted by a review of the design of the flight control systems on Model 737 series airplanes. The actions specified by this AD are intended to prevent jamming of the aileron control system during flight due to fracturing of the springs in the aileron centering units; this condition, if not corrected, could result in reduced lateral control of the airplane.
AD 97-04-11 · published Feb 18, 1997, effective Apr 4, 1997
Air Tractor, Inc. Models AT-802 and AT- 802A Airplanes
This amendment adopts a new airworthiness directive (AD) that applies to certain Air Tractor, Inc. (Air Tractor) Models AT-802 and AT-802A airplanes. This action requires revising the Airworthiness Limitations section of the applicable maintenance manual to change the life limit of the tail landing gear spring. This action results from analysis of the life limits of both the tail landing gear and main landing gear after a fatigue failure of the main landing gear on one of the affected airplanes. This analysis revealed that the life limit of the tail landing gear spring should be 3,000 hours time-in-service (TIS) instead of 3,500 hours TIS to be consistent with the main landing gear spring. The actions specified by this AD are intended to prevent fatigue failure of a tail landing gear spring before the life limit of the part is achieved, which could result in loss of control of the airplane.
AD 97-04-13 · published Feb 19, 1997, effective Apr 16, 1997
Mitsubishi Heavy Industries, Ltd. Airplanes
This amendment adopts a new airworthiness directive (AD) that applies to Mitsubishi Heavy Industries, Ltd., (Mitsubishi) MU-2B series airplanes. This AD requires removing the vent check valve assembly from the bulkhead between the fuel tanks. This AD results from an incident where both engines on an affected airplane failed near the end of a flight because of lack of fuel to the engines. The incident is attributed to the fuel filler caps on the top of the wings not sealing correctly. The actions specified by this AD are intended to prevent the inability of both engines to utilize the entire fuel supply because of the outboard fuel not transferring to the center tank, which could result in an uncommanded engine shutdown.
AD 97-04-09 · published Feb 20, 1997, effective Mar 7, 1997
Aerospatiale Model ATR42-300 and ATR42- 320 Series Airplanes
This amendment adopts a new airworthiness directive (AD) that is applicable to certain Aerospatiale Model ATR42-300 and ATR42-320 series airplanes. This action requires repetitive ultrasonic inspections to detect fatigue cracks of the lower lugs of the barrel of the main landing gear (MLG); and replacement of cracked lower lugs with new or serviceable ones and a follow-on inspection. This amendment is prompted by reports indicating that, due to fatigue cracking in the lower lugs of the barrel, the MLG collapsed. The actions specified in this AD are intended to detect and correct such fatigue cracking, which could lead to the collapse of the MLG.
AD 97-04-10 · published Feb 21, 1997, effective Mar 28, 1997
The Boeing Company Airplanes
This amendment supersedes an existing airworthiness directive (AD), applicable to all McDonnell Douglas Model DC-9-80 series airplanes, Model MD-88 airplanes, and Model MD-90 airplanes, that currently requires revising the Airplane Flight Manual (AFM) to include limitations and procedures to address situations in which the autopilot or autothrottle fails to disengage. That AD was prompted by incidents in which the flightcrew was unable to disconnect the autopilot or autothrottle function from the engaged position, due to a discrepancy in a microswitch that is associated with the operation of those functions. This amendment requires an inspection of the autopilot and autothrottle engage switches located in the flight guidance control panel, and installation of improved switches. Accomplishment of these actions will terminate the previous requirement for the AFM revision. The actions specified by this AD are intended to ensure that the autopilot and autothrottle disengage when commanded to do so by the flightcrew.
AD 97-04-16 · published Feb 24, 1997, effective Mar 31, 1997
Fokker Model F27 Series Airplanes Equipped With Walter Kidde Nose Wheel Steering System
This amendment adopts a new airworthiness directive (AD), applicable to certain Fokker Model F27 series airplanes, that requires increasing the torque value of the bolt that connects the gearbox housing assembly of the steering unit to the pivot bracket of the nose landing gear (NLG). This amendment also requires that periodic inspections of that torque value be incorporated into the FAA-approved maintenance program. This amendment is prompted by several reports that the dowel pins in the Walter Kidde nose wheel steering system were found broken and/or had elongated holes due to a reduced torque value of the subject bolt. The actions specified by this AD are intended to prevent such a reduction in the torque value, which could result in failure of the dowel pins in the Walter Kidde nose wheel steering system; this situation could result in reduced controllability of the airplane or the collapse of the NLG during landing.
AD 97-04-19 · published Feb 24, 1997, effective Mar 31, 1997
Saab AB, Saab Aerosystems Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB 2000 series airplanes, that requires a visual inspection to determine if rudder disconnection has occurred, and replacement of the disconnect unit with a new disconnect unit, if necessary. This amendment is prompted by reports that, due to the existing design, the disconnect unit of the rudder disconnect system inadvertently opened on some airplanes. The actions specified by this AD are intended to prevent the disconnect unit from opening inadvertently, which could lead to inadequate rudder control, if the engine fails during take-off or go-around and if the airplane is at low speed.
AD 97-02-09 · published Feb 25, 1997, effective Mar 4, 1997
Boeing Model 727 Series Airplanes
This document corrects information in an existing airworthiness directive (AD), applicable to all Boeing Model 727 series airplanes, that currently requires inspections to detect cracking of the actuator rib fitting of the inboard door of the main landing gear (MLG); and various follow-on actions. This action corrects a reference to the amendment number of a previously-issued AD, which was superseded by AD 97-02-09.
AD 97-02-04 · published Feb 26, 1997, effective Feb 26, 1997
Airbus Airplanes
This amendment supersedes an existing airworthiness directive (AD), applicable to certain Airbus Model A300, A300-600, A310, and A320 series airplanes, that currently requires an inspection of the landing gear brakes for wear, and replacement if the specified wear limits are not met. That AD also requires incorporation of the specified wear limits into the FAA-approved maintenance inspection program. This amendment requires that certain wear limits that are dependent on brake stack weight be used in conjunction with specified brake stack weights, and that maximum allowable brake wear limits for additional brake units be incorporated into the FAA-approved maintenance program. This amendment is prompted by a report that some brakes that are subject to the requirements of the existing AD have not been removed from service and by the determination of the maximum allowable brake wear limits for additional brake unit part numbers. The actions specified by this AD are intended to prevent the loss of brake effectiveness during a high energy rejected takeoff.
AD 97-05-01 · published Feb 26, 1997, effective Apr 2, 1997
Boeing Model 747-200, -300, and -400 Series Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 747-200, -300, and -400 series airplanes, that requires repetitive inspections to detect cracking of the front spar web of the center section of the wing, and repair, if necessary. This amendment is prompted by reports of fatigue cracking found in the front spar web. The actions specified by this AD are intended to prevent the leakage of fuel into the forward cargo bay, as a result of fatigue cracking in the front spar web, which could result in a potential fire hazard.
AD 97-02-06 · published Feb 27, 1997, effective Feb 27, 1997
Fokker Services, Fokker Services B.V. Airplanes
This amendment adopts a new airworthiness directive (AD), applicable to certain Fokker Model F27 Mark 050 and F28 Mark 0100 series airplanes, that requires installation of a bonding cable for the housing of the lavatory pump and filter assembly and the lavatory bowl. This amendment is prompted by a report indicating that the housing of the lavatory pump and filter assembly is not grounded properly. The actions specified by this AD are intended to prevent such improper grounding, which could result in an electrical fire and/or injury to passengers and crewmembers.
AD 97-05-04 · published Feb 27, 1997, effective Apr 3, 1997
Airbus Model A320 Series Airplanes
This amendment supersedes an existing airworthiness directive (AD), applicable to certain Airbus Model A320-111, -211, and -231 series airplanes, that currently requires replacing the existing standby generator control unit (GCU) with a new improved standby GCU. That action was prompted by reports of improper functioning of the standby GCU. This amendment requires replacement of the GCU on addition affected airplanes. For some airplanes, it also will require that a wiring modification be accomplished prior to replacement of the GCU. The actions specified by this AD are intended to prevent such improper functioning of the GCU, which could result in the loss of the standby emergency generation system.
AD 97-05-07 · published Feb 28, 1997, effective Apr 4, 1997
Lockheed Model 382 Series Airplanes
This amendment supersedes an existing airworthiness directive (AD), applicable to certain Lockheed Model 382 series airplanes, that currently requires a revision to the Airplane Flight Manual to require takeoff operation in accordance with revised performance data. That AD also requires installation of certain valve housings for the propeller governor on the outboard engines. This amendment revises the applicability of the existing AD to remove certain airplanes. This amendment also revises references to a certain replacement part number of a valve housing. The actions specified by this AD are intended to ensure that the airplane maintains adequate thrust decay characteristics in the event of critical engine failure during takeoff.
AD 97-02-12 · published Feb 3, 1997, effective Apr 4, 1997
Rolls-Royce plc RB211-535E4 and -535E4- B Series Turbofan Engines
This amendment adopts a new airworthiness directive (AD), applicable to Rolls-Royce plc RB211-535E4 and -535E4-B series turbofan engines, that requires installation of an improved fuel flow governor that incorporates revised minimum compressor discharge P4 stop settings. This amendment is prompted by reports of engine rundowns during low idle descent during icing conditions. The actions specified by this AD are intended to prevent compressor stall and subsequent engine rundown on one or both engines.
AD 97-02-13 · published Feb 3, 1997, effective Apr 4, 1997
Pratt & Whitney Division Engines
This amendment adopts a new airworthiness directive (AD), applicable to Pratt & Whitney JFTD12A series and T73 series turboshaft engines, that requires initial and repetitive fluorescent penetrant inspections (FPI) of compressor hubs, disks, spacers, and bolted on (rotating) airseals for cracks, and replacement, if necessary, with serviceable parts. This amendment is prompted by reports of extensive compressor rotor part cracking. The actions specified by this AD are intended to prevent disk rupture, an uncontained engine failure, and possible damage to the aircraft.
AD 97-04-12 · published Feb 27, 1997, effective Mar 14, 1997
Pratt & Whitney Canada PT6 Series Turboprop Engines
This amendment adopts a new airworthiness directive (AD) that is applicable to certain Pratt & Whitney Canada (PWC) PT6 series turboprop engines. This action requires a one-time visual inspection of compressor bleed-off valves (BOVs) to determine if an affected supplier's code number is on the cover; and, if so, this AD requires the removal of the bleed valve cover assembly from the compressor bleed valve housing assembly and inspection of the cotter pin and the guide shaft pin. If the cotter pin or guide shaft pin is not acceptable, this AD requires modifying the compressor BOV or replacing it with a serviceable part. This amendment is prompted by reports of two malfunctions of compressor BOVs that resulted in inflight engine power reduction. The actions specified in this AD are intended to prevent engine power reduction due to malfunction of the compressor BOV, which could result in a forced landing and loss of the aircraft.
AD 97-03-06 · published Feb 19, 1997, effective Mar 6, 1997
Airbus, Auxiliary Power International Corporation Appliances
This amendment adopts a new airworthiness directive (AD) that is applicable to Auxiliary Power International Corporation (APIC) Model APS3200 Auxiliary Power Units (APUs). This action requires replacement of the existing Electronic Control Box (ECB), incorporating its On Board Replaceable Module (OBRM) programmed with originally approved software version 2.0.2 or 3.2 with improved software version 4.1, or replacement of the existing OBRM of the ECB programmed with version 2.0.2 or version 3.2 with a new OBRM programmed with software version 4.1. This amendment is prompted by reports of continued fuel flow to the APU after the APU was commanded to shutdown, resulting in internal APU fires. The actions specified in this AD are intended to prevent internal APU fires due to ECB malfunction, which, if left unnoticed by flight or ground crews, could result in damage to the aircraft.
AD 97-04-15 · published Feb 20, 1997, effective Mar 7, 1997
Bombardier Inc., Kelowna Flightcraft R & D Ltd., Lockheed Martin Corporation, Pacific Scientific Company, Sabreliner Corporation, Viking Air Limited Appliances
This amendment adopts a new airworthiness directive (AD) that is applicable to certain Pacific Scientific Company, HTL/Kin-Tech Division, fire extinguisher bottle cartridges (squibs), which may be installed on various transport category airplanes. This action requires a one-time inspection of the electrical receptacle of these fire extinguisher bottle cartridges and their mating connectors to detect the presence of aluminum foil in the area of the pins of the cartridges and the connectors, and removal of any aluminum foil that is present. This amendment is prompted by a report of failure of a fire extinguisher bottle cartridge to discharge as a result of the presence of aluminum foil in the cartridge, which caused electrical shorting of the pins. The actions specified in this AD are intended to prevent such shorting, which could result in failure of the fire extinguisher bottle to discharge when commanded.
AD 97-04-04 · published Feb 21, 1997, effective Mar 24, 1997
Airbus SAS, Alliedsignal Inc, The Boeing Company Appliances
This amendment supersedes an existing airworthiness directive (AD), applicable to AlliedSignal Inc. (formerly Garrett Auxiliary Power Division) GTCP85 Series auxiliary power units (APUs), that currently requires removing the existing turbine wheel shroud and installing one constructed of Hastelloy "S" material, or installing a containment augmentation ring. This amendment deletes the option of installing a turbine shroud constructed of Hastelloy "S" material. This amendment is prompted by a report of insufficient APU containment capability with the Hastelloy "S" shroud alone installed. The actions specified by this AD are intended to prevent turbine shroud fragments from exiting the APU and puncturing the APU compartment, which could result in reduced fire extinguishing capability in the APU compartment.
AD 97-05-03 · published Feb 26, 1997, effective Mar 18, 1997
Alliedsignal Avionics, Inc. Appliances
This amendment adopts a new airworthiness directive (AD) that applies to all owners/operators of aircraft equipped with AlliedSignal Avionics Inc. (AlliedSignal) Models GNS-XLS or GNS-XL global positioning systems (GPS) Flight Management Systems. This action requires inserting a limitation into the Airplane Flight Manual (AFM) or Flight Manual Supplement Limitations Section prohibiting the use of these AlliedSignal GPS units on previously published non-precision approaches. This action is prompted by recent reports of flight course deviations because of erroneous information provided by the GPS Flight Management System. The actions specified by this AD are intended to prevent deviation from an intended flight path during a non-precision approach to an airport.
